Mode of



UNITED STATES PATENTV OFFICE.

ADDISON M. SAVVYER, OF ATHOL, MASSACHUSETTS.

MODE 0F .APPLYING STEAM-POWER T0 PROPELLERS.

Specification of Letters PatentNo. 28,200, dated May 8*, 1860.

T 0 all 'whom 'it may concern.'

Be it known that I, ADDISON M. SAWYER, of Athol, in the county of Worcester and State of Massachusetts, have invented a new and Improved Mode of Applying Steam- Power to the Propellers of Steam Vessels, of which the following is a full, clear, and exact description, reference being had to the accompanying drawings, making part of this specification, in which- Figure l,is an elevation of a hull of a vessel with the propeller attached. Fig. 2, a longitudinal section through the propeller shaft upon an enlarged scale a portion of the outline of the propeller not properly shown in the section being indicated by red lines. Fig. 3, a rear view of the propeller.

My invention has for its object to dispense with the expensive and cumbersome machinery now employed to actuate the propellers of steam vessels and consists in causing the steam to issue in jets or streams from the periphery of the blades of the propeller, thus making the latter the engine by which it is itself driven as will now be more particularly described. n

A, is t-he hull of the vessel; B, the boiler; C, the chimney, and D, the safety valve.

The propeller shaft E (Fig. 2,) seen dotted in Fig. l, is made hollow and communi- Cates by means of a pipe (F,) with the steam space of the boiler. Into the interior of this hollow shaft steam is admitted through the cock or other suitable throttle at G. At f the shaft unites with the pipe F, by a steam tight joint so packed as to permit the shaft to revolve without leaking at this point; the lower portion of the pipe where it unites with the shaft, being suitable stayed and bolted to the framework of the vessel to prevent the joint from being opened by the preS- sure of the steam or the parts from being disturbed by the thrusts of the propeller; the shaft is prevented from being displaced when the propeller is reversed by a fillet g which bears against a collar h secured to the stern post, the joint between the collar and the shaft being packed to prevent the en trance of the water. This end being furthermore insured in vessels of large class by a rear stern post between the propeller and the rudder (not shown in the drawings) from which projects a pivot which bears against the center of the propeller hub.

The propeller represented in the accom panying drawings is secured to its shaft by means of a screw head m, any other suitable device may however be adopted for this purpose. From the interior of the hollow shaft E, and through the center of each blade of the propeller pass two pipes g g2, which open out at the periphery in opposite directions and the propeller is caused to revolve by steam allowed to issue in jets or streams from the mouths of these pipes in the manner of the ancient acolipile.

Then the steam is allowed to pass through the pipes g2 and issue from the orifices l the propeller will be revolved so as to advance the vessel, but when it passes through the passages g and orifices 2 the motion of the propeller is reversed and the vessel is backed.`

To prevent the condensation of the steam in the pipes g g2, these pipes are not allowed to touch the metal of the propeller except at their extremities, the blades being made hollow to accommodate them by which means they are kept constantly surrounded by air. Any other method of packing these pipes and preventing the transmission of heat through them may be adopted.

For the purpose of regulating the admission of steam to the pipes g', g2, a hollow cylindrical valve p is employed, which when in the position represented in Fig. 2, closes the pipes g, and permits the steam to pass through the pipe g2 and issue from the orifices l.

IVhen the valve p is moved into the position indicated in red (Fig. 2) the pipes g2 will be closed and the other set (g) will be opened, when the valve isplaced in an intermediate position between t-hese two all the pipes are closed and no steam is admitted to the propeller.

The valve p is operated in the following manner: A rod L, attached to it passes forward in the hollow shaft E, and is secured by a pin M, to a sleeve N, which surrounds the shaft E, and revolves with it, but is allowed to slide thereon. The pin M, passes through slots r, in the shaft which are packed by the sleeve N, or by any suitable packing attached thereto.

The sleeve N, is moved for the purpose of shifting the valve by means of the shipping lever the forked end of which enters a groove 5 in the sleeve.

In lieu of cutting olf the steam at the interior end of the pipes g g2 I propose under certain circumstances to employ two valves at the opposite ends of these pipes and to Shift and Cut 01T the Steam at the Y:pointWhel 91?. the passage-.Qifsteemefox;ihe'purpse 0f it issues from the propeller. The valves .cegsing the same to revolve under Water thus placed Will be operated lo suitable rods vas described., Y connected with thecentra'l ro L. i 5 What I claim as myinvention and/desire Witnesses:

' "TS. ILRACI7 P. E. TESCHEMACBER.

A. M. SAWYER.

to secureby Letters Patert is; i A propeller having passages and orces i 

